The present invention relates to an articulated fitting for a vehicle seat, and to a vehicle seat having the articulated fitting.
With a known articulated fitting, the backrest of a vehicle seat in the rear of a motor vehicle can be locked in an upright seat position for people to use the seat for sitting purposes. In order to increase the loading area, the backrest can be pivoted forward into a flat table-like position.
One aspect of the present invention is the provision of improvements to an articulated fitting of the type mentioned above. According to this aspect, an articulated fitting includes upper and lower fitting parts, and the upper fitting part is for having a backrest of a vehicle seat mounted thereto. In one example, the vehicle seat is preferably rear-seat bench. The upper fitting part is mounted to the lower fitting part so that the backrest can rotate with the upper fitting part relative to the lower fitting part between at least one upright seat position and at least one other backrest position. The backrest is at least generally upright in the upright seat position, and the other backrest position is a table position, in which the backrest extends substantially horizontally, or a reclining position, in which the backrest is reclined. In accordance with this aspect, the articulated fitting further includes a control cam provided on one of the upper and lower fitting parts for interacting with a control element of the other fitting part so as to releasably secure the articulated fitting in the other backrest position. Also in accordance with this aspect, the articulated fitting includes a detent pawl pivotably mounted to the fitting part that includes the control element. The detent pawl is for moving into and out of a locking position, in which the detent pawl releasably engages the fitting part having: the control cam to releasably lock the articulated fitting in the upright seat position.
The securing of the table position by means of the articulated fitting prevents the backrest from inadvertently pivoting back, for example because of the pressure of the upholstery, which protects the transported load. The securing is to be understood as meaning that at least a rearwardly directed pivoting movement is prevented, for example by a stop or by the articulated fitting being blocked. However, there may be a certain amount of play. The same is true for a flat or oblique reclining position in which the securing is to prevent pivoting downwards. The securing may also, for example, be designed in such a manner that it prevents the backrest from pivoting forward because of a crash, in order to protect the user. By virtue of the fact that a control cam is provided on one of the two fitting parts, with the control cam interacting with a control element of the other fitting part, the locking and/or securing can be controlled by the articulated fitting. Preferably as a function of the pivoting movement of the backrest, which movement corresponds to certain sections of the control cam, in certain angular regions an unimpeded and functionally reliable locking of the articulated fitting can take place, even when the controlling components have relatively great tolerances, in other angular regions a securing can take place and in further angular regions an unimpeded pivoting of the backrest without locking can take place. In this case, the control element preferably bears at least in some sections against the control cam. Boundaries, which are designed as stops, of the various angular regions can prevent inadvertent further pivoting or pivoting back. With the articulated fitting according to the invention, there is a reduction in the structural space necessary for the installation.
In a preferred embodiment which can be produced in a structurally simple and cost-effective manner, the control cam is provided on a control plate which is arranged concentrically with respect to the axis of rotation of the upper fitting part. The control plate can be formed integrally on a fitting part, preferably the upper fitting part, or can be placed onto it and attached. Replacement of the control plate while components are otherwise unchanged or virtually unchanged enables the articulated fitting to be adapted for different applications. As a result, the production of the articulated fitting is simplified and is more cost-effective.
A control tooth is preferably provided as the control element, which interacts with the control plate, of the other fitting part. The control tooth is preferably arranged on a detent pawl for the locking of the fitting part having the control cam. In this case, the detent pawl is preferably mounted on the lower fitting part and locks the upper fitting part. The control tooth may, for example, be formed integrally with the detent pawl or may be provided on a control pawl which is formed separately and is preferably connected fixedly to the detent pawl. For the last variant, production is simplified and made cheaper.
In order to eliminate a tolerance-induced play in the bearing points, which may result in undesirable clattering, in a preferred embodiment the detent pawl locking the articulated fitting is secured by means of a moveably mounted component whose exerted force has a direction which points past the axis of rotation of the upper fitting part. The securing component then exerts on the detent pawl an additional force component which eliminates the bearing play of said detent pawl. The desired direction of force can be achieved by appropriately orientated bearing surfaces.
In the event of a crash the detent pawl locking the articulated fitting is held, preferably by positive engagement by means of a moveably mounted intercepting component, in engagement with a toothed arrangement on the fitting part to be locked. One option for reducing the loss in overlap between the locking toothed arrangements resides in this intercepting component being mounted eccentrically, for example by a bearing bolt of corresponding design. Rotating auxiliary means are preferably provided on the eccentric mounting of the intercepting component in order to set the alignment of the eccentricity relative to the detent pawl. The loss in overlap can then be reduced irrespective of manufacturing-induced tolerances.
The articulated fitting according to the invention is preferably used in a vehicle seat, in particular in a rear-seat bench in the rear of a motor vehicle, for example, of a xe2x80x9cvanxe2x80x9d, but could also be used in a front-passenger seat. The articulated fitting can have the control cam and the various play-free setting means individually or in combination.